How To: Use Biology to Create an Independence Day Bouquet

By Kim Moldofsky

Elementary School

Here’s a fun way to make a colorful bouquet that is simply to dye for. As a bonus, this decorative project comes with a simple biology lesson. We’ve all learned about how plants make their own food through photosynthesis. Of course, plants also receive water and nutrients from the soil in which they’re living. Here’s an idea for family fun that’ll teach kids about that process, transpiration, with beautiful results.


You’ll need white flowers. I like to do this with carnations because they’re affordable and work well for this experiment. I think they’re pretty, too, but I’m low maintenance like that. Prepare three vases (glasses or jars work fine) with water and the nutrient packet that came with the flowers. (If the flowers didn’t come with a supplement, mix a pinch of sugar into each container of water. Add a dash of lemon juice as well, if it’s handy.)


Add several drops of red food coloring to one of the vases, add blue to another, and leave the third as is. After cutting their stems, divide the flowers evenly among the three containers and wait. I like to start the process early in the morning so that we can observe the progress throughout the day. It doesn’t take long for the first hint of color to appear in the petals. As time passes, the petals will deepen in color.


Within 24 hours you should have a festive Fourth of July bouquet to enjoy at your own barbeque or share with a hostess.


So how did this happen? The stem of the flower contains xylem, tubes that are like a floral version of drinking straws. Stomata — small, pore like openings in the stem, leaves and petals — help the plant breathe to allow gas exchange for photosynthesis to occur. When the stomata open, moisture evaporates from the plant, pulling moisture up from the ground through the xylem, just as a person might sip a refreshing drink through a straw.


To better observe xylem, repeat this experiment with a stalk of celery. After a 24-hour soak, slice the celery in half crosswise, and you’ll get a good look at the tubes.


You can extend this activity by experimenting with different dye colors and color mixes. This activity can also go beyond merely creating a festive bouquet into a conversation about the environment. People often use the phrase, “You are what you eat,” but you can help your child understand that this applies to all living things, even plants.


Compensation was provided by Sylvan Learning. The opinions expressed herein are those of the author and are not indicative of the opinions or positions of Sylvan.